Toyota must join the ranks of Formula One's winners next season, says team technical director Mike Gascoyne.
Trulli will again partner Schumacher next season
The big-spending Japanese outfit took fourth place in the constructors' standings, with Ralf Schumacher third in the final race of the year in China.
They also had podium finishes and their first pole start through Schumacher's team-mate Jarno Trulli in 2005.
Gasgoyne said: "I think we've proved that we know what we're doing, but we've got to start winning some races."
The Briton added: "If we'd been lucky, a win was possible this year and it has to be possible next year."
Gascoyne was also left to rue Toyota's non-participation in the US Grand Prix.
They were one of seven Michelin-equipped teams that did not race, allowing Ferrari to take a maximum 18 constructors' points.
The Italian team finished third in the championship, 12 points ahead of Toyota.
"We were fourth but it should have been third," Gasgoyne admitted.
"Without Indianapolis, and really off our own backs, we should have finished third. With four or five races to go, we were quick enough to finish third."